Problem: $-5hi + 2hj + h - 10 = 7i - 7$ Solve for $h$.
Solution: Combine constant terms on the right. $-5hi + 2hj + h - {10} = 7i - {7}$ $-5hi + 2hj + h = 7i + {3}$ Notice that all the terms on the left-hand side of the equation have $h$ in them. $-5{h}i + 2{h}j + 1{h} = 7i + 3$ Factor out the $h$ ${h} \cdot \left( -5i + 2j + 1 \right) = 7i + 3$ Isolate the $h$ $h \cdot \left( -{5i + 2j + 1} \right) = 7i + 3$ $h = \dfrac{ 7i + 3 }{ -{5i + 2j + 1} }$